Figure 4.

Effect of etching time on the nanofabrication of Si(100) surface by scratching and
post-etching. The AFM image and cross-sectional profile of the nanostructure on the Si(100) surface
(a) after scratching under applied normal load Fn = 60 mN and (b to d) after post-etching in 20 wt.% KOH + IPA solution for 35 min, 40 min, and 45 min,
respectively.